Mounting plates 101

Load cells are used in a variety of applications, from structural testing in rockets to integration into advanced robotics. Mounting significantly influences the accuracy and reliability of load cell measurements. A mounting plate is a technical support base that provides a stable and prepared surface for a load cell.

These plates are more than just a simple component. They are carefully manufactured to optimize the load cell's performance by efficiently distributing the applied load across the support structure. They provide the necessary stability for the sensor to operate within its specified parameters. Mounting plates are manufactured to the most stringent specifications, often with flatness tolerances as low as 0,0002 TIR (Total Indicator Runout). This meticulous attention to detail ensures a flat, smooth support surface for the load cell, minimizing local deformation and maximizing measurement accuracy.

The special, high-quality surface of the Mounting plates from Interface overcomes common challenges such as uneven load distribution, thermal expansion and possible side loads and often eliminates the need for additional, complex assemblies.

Five reasons why mounting plates ensure accuracy and stability

Interface mounting plates are carefully engineered plates that provide additional stability and a precise foundation, essential for optimal load cell performance. A load cell is a highly sensitive sensor that detects the slightest changes in force. Even the slightest external disturbance can cause measurement errors. Mounting plates solve several key challenges, including the following five.

#1 Load Distribution – The primary function of mounting plates is to evenly distribute the applied load across the supporting structure. Without proper distribution, localized stresses can occur, leading to inaccurate readings and potential damage to the load cell and foundation.

#2 Prepared Surface – For proper operation, load cells require a flat, stable, and precisely machined surface. Mounting plates provide this ideal foundation, ensuring consistent contact and preventing irregularities in the mounting surface from interfering with measurements.

#3 Minimize deflections and crosstalk – In any force measurement system, deflections, even microscopic ones, can cause errors. This is especially important in multi-axis sensors, where off-axis loading from plate deflection can lead to apparent crosstalk between different measurement axes. Mounting plates, especially those with a special focus on stiffness, prevent such deflections, thus ensuring measurement integrity.

#4 Thermal Expansion and Side Loads – Structures expand and contract with temperature fluctuations. External forces such as wind loads or load shifts can cause significant side loads. Interface mounting plates, especially the cover plates, are designed to accommodate these movements without compromising load cell accuracy. In contrast, the high side load capacity of interface load cells often eliminates the need for separate expansion devices.

#5 Emulate calibration conditions – To achieve the most accurate results, a load cell should be used under conditions that mimic its calibration environment as closely as possible.

How Interface mounting plates achieve superior performance

Interface's commitment to precision engineering is evident in the design and manufacturing of our mounting plates. Interface mounting plates are constructed from high-quality alloy steel and stainless steel. These materials are selected for their strength, durability, and resistance under a variety of loading conditions.

While mounting plates are generally essential for compression load cells, it's important to note that they are specifically designed for this purpose and will not adequately support a general-purpose tension load cell. This underscores the special nature of these components.

Main features and advantages of interface mounting plates

• Seamless design: The interface mounting plates are designed to work seamlessly with interface load cells, ensuring optimal compatibility and performance.
• High-quality materials and machining: Manufactured with the highest quality components and processes, from material selection to precision machining, every step in the manufacturing process is dedicated to providing the highest quality and reliability.
• Performance specifications: The mounting plates are manufactured to meet the specifications of the intended product. This is a critical advantage, as they actively contribute to maintaining the accuracy and performance specifications of the load cell.
• Support: They are designed to distribute the load across the foundation of the support structure, prevent local stresses and ensure uniform force transmission.
• Contact surface: This provides a prepared surface for the load cell and guarantees a flat, stable and precisely machined interface for optimal contact.
• Easy installation: Mounting plates eliminate the need for expansion assemblies in most installations. Thanks to the top plate design and the high side load capacity of the interface load cells, external expansion mechanisms are often unnecessary, simplifying installation and reducing complexity.
• Standard and special versions: As in our Online data sheet As described above, Interface offers a wide range of mounting plates. Available in standard and custom designs: Interface offers a wide range of standard models: TP-101, TP-102, TP-103, TP-104, TP-301, TP-302, TP-303, BP-101, BP-102, BP-103, BP-104, BP-108, BP-302, BP-303, and BP-308. Interface offers customized solutions for individual application requirements.

Distinction between top and bottom plate

Base plates are typically made of mild steel and ground flat. They connect the load cell and distribute the load evenly across the foundation or support structure. They provide the load cell with a surface specifically designed for the sensor.

Top plates distribute the load, and their hard surface allows for movement due to thermal expansion, load shifting, and other lateral loads. The load cell's high side-load capacity absorbs these forces.

Double-plate (sandwich) mounting is used in situations where extremely rigid systems are required or local deformations must be minimized. A double-plate or sandwich mounting can be used. In such cases, the plates must be sufficiently thick to ensure uniform deflection.

More than just standard mounting plates: force plates

Interface continually develops innovative accessories and measurement solutions, including our force plates. These advanced systems feature multiple multi-axis sensors mounted between two plates. Force plates are ideal for applications requiring:

• Larger capacities: When a single 6-axis sensor is not sufficient for the loads used.
• Response to high moments: Their design allows them to respond effectively to significant rotational forces.
• Complex load application: Suitable for scenarios where loads are applied over a larger area, such as robot arms that provide feedback on forces during operation.

See this actual force plate application in detail. Go to Manufacturing: 6-axis force plate robot arm.